package com.study.note;

import java.util.HashMap;

public class JavaNote {
    public static void pong(){
        System.out.print("pong");
    }
    public static void main(String[] args) throws InterruptedException {

        HashMap<String,String> map=new HashMap<>();
        map.put("name",null);
        map.put("name","Jack");
        System.out.println(map.size());

        int i=0,j=0;
        if((++i>0) || (++j>0)){
            j++;
        }
        System.out.println(i+"   "+j++);

        Thread thread=new Thread(){
            @Override
            public void run() {
                pong();
            }
        };
        thread.start();
        Thread.sleep(100);
        System.out.print("ping");
    }
}
